Milling machine organization



F. A. PARSONS 2,040,528 MILLING MACHINE ORGANIZATION Filed Jan. 19, 1951 4 Sheets-Sheet l May 12, 1936.

ATTORNEY May 12, 1936- F. A. PARSONS 2,040.528

MILLING MACHINE ORGANIZATION Filed Jan. 19, 1931 4 Sheets-Sheet 2 f'g E111- 11.1

I l l l l l l l t l l l) INVEN ATTORNEY May 12, 1936. F. A. PARSONS MILLING MACHINE ORGANIZATION Filed Jan. 19, 1931 4 Sheets-Sheet 5 f) Wwf; 5w

ATTORNEY I ELI .7 l l l I I. #ww -L t NWN- 43.12.,.:3.12::., E.3513@ .h (vk wm @i u May 12, 1936. F. A. PARSONS MILLING MACHINE ORGANIZATION Filed Jan. 19, 1951A, 4 Sheets- Sheet 4 ATTOR N EY Patented May 12, 1936 UNITED .STATES PATENT OFFICE MILLING MACHINE ORGANIZATION Appiieatian January 19, 1931, serial No. 509,700

15 Claims.

This invention relates to machine tool transmission and control mechanism and more particularly to a form of such mechanism especially adapted for milling machines.

Machine tools such as milling machines require mechanism for a relativelyslow feed or cutting movement of the work relative to the cutter and it is important for various reasons that this movement shall be operative only when the tool spindle is running. There is generally provided also mechanism for a relatively fast traverse movement for quickly traversing the machine through idle or non-cutting portions of the movement cycle. During the -quick traverse movel5 ments it is preferable for a variety of reasons that the tool spindle should be stationary. Because of these different requirements it has been customary to provide separate trains to transmit the feed and the quick traverse movements from the point where the table transmission separates from the main or spindle transmission.

It is a purpose of the present invention to provide improved mechanism which will make it possible to combine the feed and quick traverse trains into a single train through at least a portion of their extent, while retaining the desirable feature mentioned above.

It is also an object to provide control mechanism of simplified operating characteristics and improved construction. In part this purpose relates to combining under a single controldevice certain functions previously ordinarily provided with separate or individual control devices, whereby a reduced number of control elements and movements are required for operating the machines through a working cycle.

The various devices shiftable for controlling the machine operation have ordinarily in the past been operated through strictly mechanical motion 10 transmitting trains, and it is a purpose of the present invention to provide improved control motion trains and more particularly of a type in part operatingby the means of a fluid or liquid.

, The control devices of a machine tool may be l5 hand or automatically operated or both, but in either event it is desirable that the elements primarily moved should move freely with little resistance and with a. resistance independent of the resistance of the members to be ilnally actu- 0 ated. It is a purpose of the present invention to provide improved mechanism for movement of the controlled parts and particularly in a form such that the part primarily moved for control purposes merely releases or controls the appli- 5 cation of a secondary power device for the iinal or resulting movement. More particularly it is a purpose to provide suchv power movement by the means 'of iiuid or liquid controlled by suitable primary control devices such as valves.

Another object is to combine the various above mentioned improvements and purposes into an organization especially suited both as to transmission and control mechanism to machine tools and particularly for milling machines.

Another object is generally to improve and simplify the construction and operation of machine tools with particular reference to milling machines and still other objects will be apparent from this specification.

The invention consists in the construction and combination as herein illustrated, described. and claimed, and in such modiilcations thereof as may be 'equivalent to the claims.

In the drawings like reference characters have been applied to the same parts in each of the several views, of which:

Fig. 1 is a right side elevation of a milling machine incorporating the invention.

Fig. 2 is a partial iront elevation oi the same machine.

Fig. 3 is a sectional view on the line 3-3 of Fig. 1 (also indicated in Figs. 4 and 5).

Fig. 4 is a sectional view on the line 4-4 of Fig. 2.

Fig. 5 is a sectional view on the line 5-5 of Fig. 2.

Fig. 6 is a diagrammatical View. in the nature o a development in which certain of the parts are shown out of their natural positions and proportions', designed to show the operation of the complete machine.

Fig. 7 is a sectional view of a. shifter device indicated in Fig. 5, showing the parts in a certain relation.

Fig. 8 is a similar view showing the parts in a different position.

Fig. 9 is a sectional view of a valve taken on the line 9-9 of Fig. 4, showing a valve member in a certain position.

Fig. 10 is a similar view showing the valve member in another position.

As shown in Fig. 1, the machine comprises a bed or base l on which is slidably mounted a head frame 2, the head frame supporting a spindle carrier 3 in which is rotatably mounted a spindle l. Overarms 5--5 are slidably supported in carrier 3 for cooperation with a tool arbor, not shown, in the usual manner. A work table 6 is. slidably supported on bed I and is movable in suitable relation to spindle 4 for tooling of a work piece fixed with the table by 'means of a cutter fixed with the spindle. Spindle 4 and table. 6 may be driven from a pulley 1 through suitable mechanism to be presently described.

Head frame 2 may be adjusted on bed I by means of a crank or the like, not shown, applied to the squared portion 8 of a screw 9 prevented from moving axially relative to bed by means of a bearing I8 and engaging a nut fixed with head frame 2.

Spindle carrier 3 may be raised and lowered in` head frame 2 by means of a screw I2, Fig. 2, fixed against axial movement relative to frame 2 in a bearing I3 and engaging a nut I4 fixed with carrier 3. Screw I2 may be turned by means of a suitable crank, not shown, applied to squared portion |5 of a shaft I6 journaled in head frame 2 and driving screw I2 through bevel gears |1 fixed respectively with shaft I6 and screw I2.

Any suitable means may be provided for clamping head frame 2 with base I and for clamping spindle carrier 3 with head frame 2. Many such means being well known and forming no part of the present invention, -they are not shown here.

The following mechanism is provided for driving spindle 4 from pulley 1. Referring to Fig. l, pulley 1 is journaled on a sleeve |8 which it drives through the medium of a clutch, generally denoted by numeral |9 and which is journaled in a suitable bearing 20 in bed I and drives a shaft -2| rotatably tted in the bore of sleeve I 8 through a clutch, generally denoted by numeral 22, shaft 2| driving a vertical shaft 23 through bevel gears 24 and 25 fixed with shafts 23 and 2| respectively. Shaft' 23 is journaled in suitable bearings in head frame 2 and drives a shaft 26 through a rate changer, generally denoted by numeral 21, shaft 26 driving a s'haft 28 through gears 29 and 38 fixed with the respective shafts and shaft 28 driving spindle 4 through bevel gears 3| and 32 fixed respectively with shaft 28 and spindle 4. Clutch IScomprises a member 33, Figs. 1 and 6, slidably keyed with sleeve I8 and having a tapered friction surface 34 adapted to engage a complementary surface on the inside of pulley 'l and capable of being moved into and out of ,engage- -ment therewith by means of a hand lever 35 pivoted on a stud 36 xed with bed-I. Member 33 has an annular groove 31 engaged by a pin- 38 fixed with a lever 39 pivoted on a stud 40 fixed with bed I and a rod 4| pivotally connects the ends of the levers whereby movement of lever 35 to the left in Fig. 1 will disengage clutch I9, while movement thereof to the right will engage the clutch, 'as will be understood. Clutch 22 comprises a driving member 42 fixed with sleeve I8 and a driven member 43 fixed on shaft 2|. A plurality of friction discs 44 are disposed between members 33 and 43, alternate discs being slidably xed with members 42 and 43. The discs may be pressed into mutual driving relation by means of levers 45 pivoted on an adiustable nut 46 adjustable with relation to member 43. The levers on actuation press against a plate 41 slidably keyed with member 43 compacting the discs into mutual driving relation and thereby causing transmission of motion from member 42 to member 43 and shaft 2|. For actuating levers 45 a spool 48 is slidably keyed with shaft 2| and adapted, when moved to the right in Fig. 1, to cause such actuation of levers 45.

Toallow longitudinal motion of head frame 2 gear '25-'i 's,slidably keyed on shaft 2| and has a hub 49 `j o'urnaled in a bracket 58 depending from head frame 2 through a suitable slot in bed I.

the projecting upper end of the shaft.

A brake, generally denoted by numeral 55, is provided for promptly bringing the above described parts to a stop under certain conditions.

and comprises a stationary member 56 fixed with a part of bed I and a movable member 51 fixed with shaft 2|. A series of friction discs 58 are disposed between members 56 and 51, alternate` discs being slidably keyed with member 56 and.

the remainder with member 51. The discs may be compacted into frictional contact by means of levers 59 pivoted on a collar 6u longitudinally adjustable on shaft 2 I. Levers 59 may be actuated by a movement to the left, in Fig. 1 of spool 48, and pressed against a plate 6|, forcing the same against discs 58. The proportionsof spool 48 are such that clutch 22 is necessarily disengaged before brake 55 is applied. Spool 48 is moved to the right or left by means of mechanism to be presently disclosed.

The following mechanism is provided for driving table 6 from pulley 1. Sleeve I8 has fixed therewith a gear 62 which drives a gear 63 through an idler 64 journaled on a suitable stud fixed with bed I, gear 63 driving a shaft 65 through an overload releasing device, generally denoted by numeral 66. lShaft 65 drives a shaft 61 through a rate changer, generally denoted by numeral 68, shaft 61 driving a wormwheel 69 journaled on a shaft 10 by means of a worm 1| journaled on shaft 61 and driven therefrom through an overload release, generally denoted by numeral 12.- Worm wheel 69 constitutes the terminus of the feed train and as shown in Figs. 2 and 6 drives a table screw 13 through a clutch device, generally denoted by numeral 14, a reverser, generally denoted by numeral 15, anda sleeve 16 slidably keyed with table screw 13.

Overload release 66, Fig. l, comprises a clutch member 11 slidably keyed with shaft 65 forced into driving relation with a clutch member 18 fixed with gear 63 by means of a spring 19 bearing at one end against a collar fixed with shaft 65 and at the other end against clutch member 11, the teeth 8| of the clutch members being of such form as to allow relative motion therebetween in case the torque transmitted exceeds a predetermined amount. A collar 82 fixed with shaft 65 takes the resulting thrust of gear 63, thus eliminating the continuous friction which would otherwise result from the pressure of the spring and gear against stationary parts of bed Rate changer 68 comprises'gears 83 and 84 removably keyed with shafts 65 and 61 respectively, within a suitable housing having a cover 85 allowing access to the gears. The gears may be removed and interchanged or replaced with others of different ratios, also mutually interchangeable to provide a plurality of rates in shaft 61.

Overload release 12 comprises a clutch member 86, slidably keyed to shaft 61 and urged into driving relation with a clutch member 81 fixed with worm 1| by means of a spring 88. Spring 88 bears at one end against member 86 and at the other end against a collar 89 xed with shaft 61. Clutch members 86 and 81 are provided with complementary clutch teeth so shaped as to cause a positive transmission of motion therebetween so long as the torque transmitted does not exceed a predetermined amount, but in the event that it does, to cause clutch member 86 to be forced to the left in Fig. l whereby the teeth will slip by each other, thus interrupting the drive and preventing damage. l

It might appear that overload release device 12 would be unnecessary in view of the provision of overload release device 66, but this is not true,` owing to the provision of rate changer 68 between the shafts, since at such times as a gear ratio were in use, which would result in driving shaft 61 at a reduced rate relative to the shaft 65, the torque which it would be possible to develop in shaft 61 would be that in shaft 65 multiplied by such ratio, and might reach a value sufficient to cause damage before release device 66 would operate. Under such conditions release device 12 would operate Aand save the machine or work from damage.

I On thecontrary, if the ratioI of rate changer 68 were such as to drive shaft 61 at a higher rate than shaft 65, the torque in shaft 61 would be less than in shaft 65 and upon overload the torque in shaft 65 might reach a dangerous value beffore device 12 would operate. In such a case device 66 would function and prevent damage to any part of the feed train.

A rapid traverse train for driving table 6 originates in a gear 90 fixed with shaft 65. Gear 90 drives a shaft 9| through an idler 92 journaled on.

a suitable stud fixed with bed I and meshing with a gear 93 xed with shaft 9|. Shaft 9| drives a bevel gear 94, Figs; 2 and 6, through a bevel gear 95 fixed with the shaft, gear 94 being journaled on shaft and having a hub portion 91 provided with suitable clutch teeth adapted to engage member 14 upon movement thereof to the leftl in Figs. 2 and 6. 'Ihe dimensions of member 14 are such that it is impossible to engage it with both worm wheel 69 and bevel gear 94 at the same time. Accordingly, movement of member 14 to the right will cause its engagement with worm wheel 69 and rotation at a relatively slow rate, while movement of member 14 to the left will cause its engagement with bevel gear 94 and rotation at a relatively fast rate. Member 14 has a gear 98 fixed therewith adapted tov drive reverser 15. A

Reverser comprises gears 99 and |00 spaced apart and journaled on a shaft |0| and having hub portions |02 and |03 respectively, provided with clutch teeth adapted to cooperate with suitable clutch teeth on a shiftable member |04 slidably journaled on shaft |0| between gears 99 Member |04 is provided with a gear |05 adapted to mesh with gear 98 on member 14. Member |04 may thus be moved longitudinally on shaft l0| to engage and drive either gear 99 or |00, the faces of gears 98 and |05 being suiiiciently Wide to allow a suitable amount of axial motion of the members without impairing the driving relation therebetween. Gear |00 drives sleeve 16 through a gear |06 meshing with gear |00, while gear 99 drives a gear |01 also fixed with sleeve 16 through an idler |08, (Fig. 1) journaled on a suitable stud fixed with bed Consequently when member |04 is engaged with gear |00, sleeve 16 and table screw 13 will be rotated in one direction and when member |04 is engaged with gear 99, they will be rotated in the opposite direction. Table screw 13 is journaled in suitable bearings |09|09 and thereby fixed against axial movement relative to the table. Screw 13 engages a nut ||0 fixed with bed whereby rotation of screw 13 will cause sliding movement of table 6.

The above outlined shiftable members in the present instance are controlled by mechanism actuated by uid pressure. The fluid pressure originates in a pump and accumulator, generally denoted by numeral l, Figs. 3 and 4, and passes through a duct ||2 having a branch ||3 leading to a control valve, generally denoted by numeral ||4 from which it is conducted to a clutch shifter, generally denoted by numeralA |5, Fig. 6, through pipes ||6 and ||1. Fluid is conducted also from valve ||4 to a rapid traverse shifter, generally denoted by numeral ||8 through pipes ||9 and |20. Another branch |2| from duct ||2 leads to a reverser shifter, generally denoted by numeral |22. l

Pump may be of any suitable type, but in the present instance consists of gears |23 and |24, Fig. 3, mashed together in a substantially closed casing having an inlet port |25, Fig. 6, and an outlet port |26. Gear |24 is fixed with a shaft |21, Fig. 1, and driven from shaft 65 through a gear |28 meshing with gear 90. An accumulator cylinder |29, Fig. 3, is associated with the casing of the pump and has a piston |30, movably fitted therein and pressed to the left in Fig. 3 by means of a spring |3|. Inlet port |25, Fig. 6, communicates with cylinder |29 at a point to the right of piston |30 and a port |32 communicates from a point substantially opposite port with a suitable reservoir 33, Figs. l and 3. Accordingly pump receives fluid through ports |32 and |25 and forc'es it through discharge port |26, a check valve |34, and a port |35 to cylinder |29 at a point to the left of piston |30. The accumulation of iiuid to the left of piston forces the same to the right against the pressure of spring |3| and when a predetermined amount of fluid has been forced into cylinder |29 in this manner, piston |30 covers port |25 and prevents access of iiuid to the suction side of the pump. Since fluid pressure is prevented from acting backwardly from port against the pump by check valve I 34, and -since no fluid is admitted to the pump through port |25, the pump will be relieved from load at such times as a predetermined accumulation of iiuid is present in cylinder |29 sufficient to .satisfy the needs of the various Shifters.

Valve ||4 comprises a rotatable plug |36, Figs. 6, 9, and 10, fitted in a bore |31. Fluid fro-m pipe ||3 enters bore |31 through a port |38 and with Valve member |36 in the position shown in Fig. 9 passes through a port |39 to a passage |40 connecting with pipes and |9 leading to Shifters ||5 and ||8. Any iiuid returned from Shifters ||5 and ||6 through pipes ||6 and |23, respectively, passes through a passage 4| and enters bore |31 through a port |42 passing through a bore |31 to a port |43 leading back to reservoir |33 as shown in Fig. 4. With valve ||4 in the position shown in Fig. 10, fluid from pipe ||3 will be directed through port |42 and passage |4| to Shifters ||5 and ||8 through pipes ||6 and |20, respectively, and any iiuid returning from shifters ||5 and ||8 through pipes ||1 and I|9 will pass through passage and port |39 to bore |31 and return to reservoir |33 through port |43.

Clutch shifter ||5 comprises a plunger |44, Fig. 6, fitted for reoiprocatory movement in cylinders |45 and |46 connected respectively with pipes ||6 and ||1 through ports |49 and |50.

The plunger has xed therewith a shifter fork |5| engaging a suitable groove |52 in spool 48. Accordingly, when fluid is admitted to cylinder |46 and exhausted from cylinder |45, plunger |44 will move upwardly in Fig. 6, thereby engaging clutch 22, while when fluid is admitted to cylinder |45 and exhausted from cylinder |46, plunger |44 will be moved downwardly in Fig. 6, thereby disengaging clutch 22 and applying brake 55.

Rapid traverse shifter ||8 comprises a plunger |53 slidably tted in cylinders |54 and |55 fixed with bed and connected respectively with pipes ||9 and |20 through ports |56 and |51. Plunger |53 has a shifter fork |58 fixed therewith and engaging the sides of gear 98, whereby motion of plunger |53 will cause shifting of' member 14. Accordingly, when fluid is admitted to cylinder |54 and exhausted from cylinder |55, member'14 will be engaged with worm wheel 69 for driving table 6 at a feed rate, while when fluid is admitted to cylinder |55 and exhausted from cylinder |54, member 14 will be moved into engagement with bevel gear 91 for driving table 6 at a rapid traverse rate.

Valve plug |36 may be moved by means of a hand lever |59 fixed with a shaft |60 journaled in bed and having a sector |6| fixed therewith and engaging a gear |62 fixed with plug |35. Thus when lever |59 is moved to the left, Figs. 2 and 6, valve plug |36 is turned to the position shown in Fig. 9 and fluid is admitted to port |39, flowing through pipes |1 and ||9, causing engagement of clutch 22 and shifting member 14 into engagement with worm wheel 69. When, however, hand lever |59 is moved to the right, valve plug |36 is turned to the position shown in Fig. 10, and uid is admitted to port |42, passing through pipe ||6 and causing disengagement of clutch 22 and application of brake 55, thus bringing spindle 4 promptly to a` stop. At the same time, fluid passes through pipe |20 causing plunger |53 to shift member 14 to the left, disengaging it from worm wheel 69, and engaging it with .bevel gear 91, thus shifting from a feed drive rate to a rapid traverse rate.

Reverser shifter |22 operates independently of valve 4. The shifting is done by action of fluid pressure from pump acting on a plunger |63 slidable in cylinders |64 and |65. Plunger |63 has a member |66 fixed therewith and connecting with a rod |61 leading to a shifter fork |68 engaging the sides of gear |05 whereby movement of plunger |63 will cause corresponding movement of gear |05 and member |04. The action of the fluid in cylinders |64 and |65 may be controlled by the han'd lever |69 fixed with a shaft |10 journald in bed and actuating a stem |1| through a gear |12 fixed with shaft |10 and engaging a rack portion |13 of stem |1|. StemA |1| is slidably fitted in coaxial bores formed in plunger |63 and in portions |14 and |15 of the cylinder member cooperating with the bores to form valve means for effecting such control, the bore in plunger |63 being denoted by numeral |16.

Fluid is admitted to cylinders |64 and |65 from pipe |2| through an elongated port |11 registering at all times with a reduced portion |18 of stem |1|. It then enters an opening |19 communicating with a bore axially formed in stem |1| and escapes through an opening |8| into an annular groove |82 formed in stem |1|. Fluid also passes further in bore |80 and escapes through an opening |83 into a second annular groove |84. A cut-away portion |85 of stem |1| forms pistons |86 and |81 separating grooves |82 and |84 from cut-away portion |85 and provides an exhaust chamber for used fluid. An exhaust port |88 is formed through the wall of plunger |63 in position to register with cut-away portion |85 in the various relative positions of plunger |63 and stem |1|. A port |89 leads from a predetermined point in bore |16 through plunger |63 to the interior of cylinder |64 and a port leads from another point in bore |16 tlgough plunger |63 to the interior of cylinder Ports |89 and |90, when plunger |63 and stem |1| are in their respective mid-positions, enter bore |16 substantially opposite pistons |86 and |81. The device is accordingly stable in this position since fluid is prevented from passing from groove |82 into port |89 or from groove |84 into port |90 by pistons |86 and |81 respectively. If now stem |1| is moved, for example to the right, by the action of the gear |12, fluid will be admitted from groove |82 to port |89, flowing into cylinder |64 and tending to force plunger |63 also to the right. In the meantime, iiuid al ready in cylinder |65 will pass out through port |90 into exhaust chamber |85 and escape through port |88, stem |1| having moved suiliciently to establish registration between port |90 and chamber |85. This action will continue until plunger |63 moves sufliciently to reestablish the relation with stem |1| which obtains in Fig. 6, when ports |89 and |90 will be again closed by pistons |86 and |81 and the movement will stop.

If, on the other hand, plunger |63 be displaced from itscentral position, for example to the left in Fig. 6, uid will be immediately admitted from groove |82 to port |89 as before and plunger |63 will again be moved to the right until it has taken a position in which ports |89 and |90 are again closed by pistons |86 and |81.

Plunger |63 will accordingly operate to shift member |04 in accordance with the movements of hand lever |69 as communicated to stem |1|.

In the event that plunger |63 or member |04 should stick in one of the engaged positions, for example to the right, it is possible that steml |1| might be moved, for instance, to its extreme left position before plunger |63 would move from its extreme right position. The relation of pistons |86 and |81 to each other and the length of stroke of the parts `is such that the above described action of the fluid will still be carried out as is clearly apparent from Fig. 7 wherein the plunger is shown in its extreme right position and the stem in its extreme left. If it proves to be desirable to maintain plunger |63 under a denite pressure when at either end of its travel, this may be done by making the travel of stem |1| slightly greater than the maximum travel of plunger |63 in either direction from central position. The result of this is clearly shown in Fig. 8 in which even though plunger |63 is moved to the limit of its leftward travel, communication is still open from groove |84 to port |90 and fluid pressure is acting continuously in cylinder |65 while cylinder |64 is open to the exhaust through port |89, chamber |85, and port |88.

This over travel of -stem 1| is not necessary, however, since, as above outlined, plunger |63 will take up a position after each movement in which ports |89 and |90A are substantially opposite pistons |86 and |81. It is automatically prevented from being displaced from this position and accordingly its travel is always substantially of the pins into the path of movement of dogs |94 and v|95 respectively, Fig. 2, which are adjustably xed on the front edge of the table by means of a T-slot |96 and T-bolts |91 and |98 in the usual manner. The-pins |92 and |93, for reasons to be explained later, stand at different distances from the edge of the table and the dogs have beveled pin contacting portions suitably spaced from the table to correspond with the respective pins. The shaft |60 is provided with a cam |99 xed thereon and adapted to co-act with a pointed plunger 200 which is pressed upwardly by a spring 20|. The arrangement is such that when the valve ||4 is in the one or the other position, the point of the plunger rests on the one or the other side of cam |99, and when shifted to change to the other position, the plunger is forced downwardly as the shaft |60 turns, until the point of the cam moves past the point of the plunger, after which themplunger reacts on the cam to quickly shift the valve to its opposite position. As previously noted, either direction of movement will move one of the trip pins|92 or |93 up into the path of movement of one of the dogs |91 or |68 and the proper dog may be positioned to contact the raised pin Vduring the continued movement of the table and move it down again until the point of cam |99 has passed plunger 200, as above described. The plunger then quickly completes the valve movement, thus actuating Shifters ||5 and ||8 and changing the rate of movement of the table, and at the same time raises the other plunger into the path of the other dog where it may later be contacted to similarly change the rate again. Thus during movement of the table in either direction, the rate may be changed at any point, and as often as desired, by suitably positioning suitable dogs similar to dogs |91, |98.

It may occur that rate changes are desired during one direction of table travel which are not desired at corresponding positions in the opposite direction of table travel. In such case dogs are used of a type having plunger contacting portions hinged to be effective in only one direction of table travel, but since such hinged dogs are well known in the operation of mechanically actuated supports, examples thereof are not here shown.

Power movement is provided for reverser shifter |22 for which the mechanism is as follows: Shaft |10, Fig. 6, above mentioned, is journaled in a sleeve 202 which is in turn journaled in bed Sleeve 202 is provided with ears or`1ugs 203 and 204, Fig. 2, which carry adjustable screws 205 and 206 respectively, adapted to contact with opposite sides of a lug 201 xed with shaft |10. The screws 205 and 206 may be adjusted to permit a considerable movement of sleeve 202 in either direction before the points of the screws contact the lug 201 to move shaft |10. Sleeve 202 extends into bed and has lfixed therewith a gear 208, Fig. 6, upon opposite peripheral sides of which a plurality of trip pins or plungers 209 and 2|0 are engaged by suitable rack teeth. The arrangement is such that the pins are moved' oppositely when sleeve 202 is moved, and a movement of sleeve 202 to a position for table movement to the right in Fig. 2 will move the left-hand pin upward and the other pin downward, and vice versa. Fixed on -sleeve 202 outside of bed is a cam 2| Fig. 2,

configurated to provide a central notch 2| 2 and 'high points 2|3 and 2|4 on each side of the notch. A pointed plunger 2|5 co-acts with cam 2|| under pressure of a spring 2|6. When sleeve 202 is moved in either direction to move the cam points 2| 3 and 2|4 past the point of plunger 2|5, the cam and plunger will cooperate under pressure of spring 2|6 to continue the movement ofsleeve 202 until stem |1| has been moved to the fullI extent of its movement in such direction.

The construction described provides an adjustable lost motion -device interposed in the transmitting connections between pins 209 and 2|0 and stem |1|, but not between hand lever |69 and stem |1-|.

Dogs 2|1 and 2|8, Fig. 2, are adjustably iixed on the front of the table by means of T-slot |69 and T-bolts 2|9 and 220 in the usual manner and are each provided with portions suitably positioned to contact with pins 209 and 2|0 during the travel of table 6in the one or the other direction. The contact portions may be made of such dimensions as to force the pins contacted downward to any desired extent sufficient to move sleeve 202 until the notch of cam 2|| has been moved past the point of plunger 2|5 in either direction of travel by the one or the 'other dog. However, it will occur that if the screws 205 and 206 are suitably adjusted, plmger |63 and member |04 will be moved to a neutral position before this happens, and the table will cease to move while the 4plunger is still engaged in the notch which will yieldably hold the parts in such position until lever |69 has been manually operated. It is to be noted, however, that the lever cannot be operated to continue table movement in the same direction because prevented by contact with thepin and the dog which has just forced it down, but table movement may be reestablished in the opposite direction by continuing the movement started by the dog until the cam notch will have passed the' plunger, when the cam and plunger will 4 quickly move the parts under pressure from spring 2|6. Such is the operation if the screws 205 and 206 are adjusted to provide little or no lost motion between the ends of the screws and a lug 96, but if 'adjusted to provide considerable lost motion, so much as may be necessary to permit the central notch 2 I2 to move completely past the point of the plunger before the plunger |63 and member |04 have reached a neutral position, then immediately before the parts reach a neutral position, the cam and plunger will cooperate under the pressure of the plunger spring and continue the movement of the parts through such neutral position until the opposite positionis reached, and the table will immediately start to move in the opposite direction. Thus either a stop or a reversal of table movement may be effected at either end of the table stroke inA accordance with the adjustment of screws 205 and 206. The screws may both be adjusted to give a reversal of table movement,

cause a stop at the one end of the table travel and the other screw to eiect a reversal of table movement. Thus the table may, for instance, be started by hand movement of lever H59 to travel to the left in Fig. 2, and after completing the desired left movement, dog 2l8 will strike plunger 2l0, and, screw 20S being properly adjusted, the table movement will be reversed. The table then travels to the right until the starting point is reached, when dog 2H contacts plunger 209 and, screw 205 being properly adjusted, the table stops. This constitutes an automatic cycle of forward and return movement which may be performed in either direction.

'Ihe handle I 69 is connected directly to shaft |10 without motion being transmitted through the lost motion connection, as previously noted, and thus even through the lost motion device is adjusted to provide table reversal when the parts are dog actuated, table movement may always be interrupted at any point by positioning the hand lever centrally.

It will be noted that the rate change trip plungers I92 and l93 are spaced at different distances from the front edge of table 6. This is in order that the dogs eiective on the respective plungers will not contact the other plungers on the continued or return movement-of the table. Reverse plungers 209 and 2| 0 are also spaced at different distances from table 6 than rate changer plungers |92 and |93, as shown in Fig. l, whereby rate change dogs |94 and |95 may be placed between reverse dogs 2I1 and 2|8 when desired without interfering with the reverse plungers 209 and 2|0.

The above being a full and complete description ol' a machine illustrative of the invention, what is claimed is:

1. In a milling machine, the combination of a reciprocable worktable, a supporting structure therefor, a rotatable tool spindle at a level above said table and axially transverse to the path of table movement, said structure providing a spindle y supporting portion uprising adjacent a longitudinal edge of said table and at one side of a vertical plane passing through said edge; a spindle train including a power source, a motion interrupting means, a rate changer and saidspindle serially connected in the order recited, a transmission for movement of said table driven from the said power source to exclude said interrupting means and including in the order recited a plurality of branch lines one of which includes a feed rate changer, a device shiftable to be selectively driven from the one or the other of said branch lines, a reverser and said table, said reverser being positioned adjacent to said table, and control mechanism for said machine including dog operable means adiacent said table, a connection from said dog operable means for the operaf tion of said reverser, manually operable means having a portion positioned at the other side of said vertical plane and adjacent the other longitudinal edge of said table, connections from said manually operable means for the operation both of said shiftable device and said motion interrupting means.

2. In a. milling machine, the combination of a tool spindle, a work support, a support for'said spindle, one of said supports being movable in a path transverse to the axis o'f said spindle, a power train for movement of said spindle including a power source, a motion interruptor, transmission means for movement of said support driven to exclude said interruptor including a plurality of branch lines one of which includes a feed rate changer, a device shiftable to be selectively driven from the one or the other of said branch lines and a reverser shiftable to cause movement of said support selectively in one or the other direction, and control means including a rst controller adapted to dependently operate said motion interruptor and said device, and a second controller for controlling said reverser and operable -independently of said ilrst controller each of said controllers comprising a. primary control means and secondary control means including fluid operable shifters controlled from said primary control means.

3. In a milling machine, the combination of a reciprocable work table, a supporting structure therefor, a rotatable tool spindle at a level above said table and axially transverse to the path of table movement, said structure providing a spindle supporting portion uprising adjacent a longitudinal edge of said table and at one side of a vertical plane passing through said edge, a power source associated with said machine, transmission means for driving said spindle including said power source, a motion interruptor and a rate changer serially connected between said power source and said spindle, a transmission for movement of said table including a plurality of branch lines each driven from said spindle transmission to exclude said motion interruptor, a selector shiftable to be selectively driven from the one or the other of said branch lines and a train connecting said selector with said work table and including a. reverser adjacent said table and selectively shiftable into positions to cause movement of said table in one or the other direction, and control means including a rst controller having a motion .transmitting connection for shifting of said reverser, and a second controller operable independently of said rst controller and including a motion transmitting connection to said shiftable selector, a iiuid operable shifter for actuation of said motion interruptor, a valve controlling said uid operable shifter, and a motion transmitting connection to said valve, whereby said second controller is operable for dependent operation of said shiftable selector and said motion interruptor, each o'f said controllers having portions exposed at the other side of said vertical plane and adjacent the other longitudinal edge of said table, and dogs xed with said table and adapted to contact said exposed portions at predetermined points in table movement.

4. In a milling machine, the combination of a tool spindle, a work support, a support for said spindle, one of said supports being movable in a path transverse to the axis of said spindle, a power train for rotation of said spindle including a motion interruptor and a power source, control means for said motion interruptor including a fluid operable shifter device, transmission means for movement of said support drivenV from said power source exclusive of said motion interruptor, and including a feed rate train, control means for said transmission including a device, shiftable for altering the transmission effect, a source of uid supply for said iluid operable shifter, valve means controlling the supply of fluid to said fluid operable shifter, and a controller connected 'for simultaneous operation of said valve means and of said shiftable device.

5. In a milling machine, the combination of a reciprocable work table, supporting structure therefor, a rotatable tool spindle at a level above said table and axially transverse to the path of table movement, said structure providing a spindle supporting portion uprising adjacent a longitudinal edge of said table and at one side of a vertical plane passing through said edge, a power source associated with said machine, transmission means for driving said spindle from said power source including a motion interruptor and rate changer serially connected between said power source and said spindle, a feed train driven from said transmission at a point between said power source and said motion interruptor and including a feed rate changer, a rapid transverse train driven from said transmission at a point between said power source and said selector means shiftable to be selectively driven from the one or the other of said trains, a train connecting said selector means and said table including a reverser adjacent said table, and control means including a plurality of separately operable controllers each having a portion exposed adjacent the other longitudinal edge of said table, a connection from one of said controllers to said reverser, another connection from the other of said controllers to said selector and to said motion interruptor, and means fixed with said table adapted to contact said exposed portions at predetermined points in the travel of 'said table.

6. In a vmilling machine, the combination of a rotatable spindle, a support therefor, a second support, one of said supports being movable with respect to the other support, a power train for rotating said spindle including a power source and a motion interruptor, a transmission for said movable support including a plurality of branch lines each driven from said power train at a point between said power source and said motion interruptor, one of said branch lines including a feed rate changer, a selector shiftable to be driven selectively from one or the other of said branch lines, and a train connecting said selector With said movable support and including a reverser, co-ntrol means including a rst controller for dependently operating said selector and said motion interruptor, and a second controller for said reverse: and operable independently of said first controller, each of said controllers including primary control means and secondary control means including power operated Shifters, responsive to said primary control means.

7. In a milling machine, the combination of a reciprocable work table, a supporting structure therefor, a rotatable tool spindle supported at a level above said table and axially transverse to the path of table movement, said structure providing a spindle supporting portion uprising ad'- jacent a longitudinal edge of said table and at one side of a vertical plane passing through said edge, a power source associated with said machine, transmission means for driving said spindle therefrom including a clutch and a rate changer serially connected between said power source and said spindle,a power train driven from said transmission means at a point, between said power source and said clutch and adapted to drive said table at a feed rate, a second power train driven from said transmission means at a point between said power source and said main clutch and adapted to drive said table at a rapid traverse rate, a reverser shiftable into positions to cause movement of said table selectively in one or the other direction, means including a fluid operable shifter adapted to cause shifting of said reverser, a selector device adapted to determine which of said trains shall be effective to drive said table through said reverser, means including a fluid operable shifter adapted to cause actuation of said device, a fluid operable shifter for actuation of said main clutch, a train actuable for causing operation of certain of said Shifters for shifting said reverser, a train actuable to cause operation of certain of said shifters for causing dependent operation of said selector device and said main clutch, said trains having portions exposed adjacent the other longitudinal edge of said table, and dogs fixed with said table and adapted to contact said exposed pcrtons at predetermined points in table movement whereby to actuate said trains.

8. In la machine tool, the combination of a rotatable spindle, a support therefor, and a second support, one of said supports being movable with respect to the other support, a power train for rotating said spindle including a power source and a main clutch, a feed transmission for movement of said support driven from said power train at a point between said power source and said clutch, a rapid traverse transmission for movement of said support driven from said power train at a point between said power source and said clutch, a selector shiftable to cause movement of said support from one or the other of said transmissions, a reverser shiftable to selectively cause said support to be driven in one or the other direction, primary control means for dependently operating said selector and said main clutch, primary control means for controlling said reverser separate from the above mentioned control means, secondary control means including fluid operated Shifters controlled from said primary control means and adapted to actuate said main clutch, said selector and said reverser, and means including a pump driven from said power train at a point between said power source and said main clutch and adapted to supply fluid to said secondary control means.

9. In a milling machine. the combination of a base, a work support movably supported from said base, a tool spindle disposed at a level above said work support and axially transverse to the -path of movement thereof, means for supporting said'spindle including a member uprising from said `base adjacent a longitudinal edge of said work support, and a spindle carrier adjustably supported from said member and adapted to support said spindle, a power train for rotating said spindle including a power source and a main clutch, a transmission for movement of said work support at a feed rate driven from said power train at a point between said power source and said clutch, a transmission for movement of said work support at a rapid traverse rate driven from said power train at a point between said power source and said clutch, a device shiftable to selectively cause movement of said support from the one or the other of said transmissions, a reverser shiftable 'to cause actuation of said work support from one of said transmissions selectively in one or the other direction, primary control means situated adjacent the other longitudinal edge of said Work support for dependently operating said device and said main clutch, primary control means also situated adjacent such edge of said work support for controlling said reverser separate from the above mentioned control means, secondary control means including fluid operated Shifters responsive to said primary control means and adapted to actuate said main clutch, said device, and said reverser means, a pump driven from said power train at a mint between said power source and said main clutch and adapted to supply iiuid to said secondary control means, and means adapted to automatically operate said primary control means in response to movements of said work support.

10. In a machine tool, the combination of a rotatable spindle, a support therefor, and a second support, one of said supports being movable with respectl to the other support, a power train for rotating said spindle includinga power source,

a main clutch and said spindle in the order recited, a 'feed transmission for movement of said support at a feed rate, and a transmission for movement of said support at a rapid traverse rate, said transmissions having a portion common to each other and driven from said power train at a point between said power source and said clutch, an overload release device associated with said common portion, a selector shiftable to cause actuation of said support from either of said transmissions, a reverser shiftable to cause actuation of said support selectively in either direction, and a second'overload release device associated exclusively with said feed transmission.

11. In a machine tool, the combination of a rotatable spindle, a support therefor, and a second support, one of said supports being movable with respect to the other support, a power train for rotating said spindle includingl a pwer source, a clutch, a. second clutch and said spindle in the order recited, a feed transmission for movement of said support at a feed rate, a rapid traverse transmission for movement thereof at a rapid traverse rate, said transmission having a common portion driven from said power train at a point between said clutches, 'an overload release' device associated with said common portion, a selector shiftable to cause actuation of said support from either of said transmissions, a reverser shiftable to cause actuation of said support selectively in either direction, and a second overload release device associated exclusively with said feed transmission.

12. In a milling machine, the combination of a .rotatable tool spindle, a support therefor, a work table reciprocable adjacent said spindle in a path transverse to the spindle axis, a spindle transmission including a power source and a motion interruptor, a table transmission including a feed rate branch line and a quick traverse rate branch line each driven from said spindle transmission exclusive of said motion interruptor, a selector shiftable to be driven from the one or the other of said branch lines and a train connecting said selector with said table and including a. motion reverser, a controller providing a motion transmitting connection with said reverser, and a second controller operable independently of the rst mentioned controller and providing a motion transmitting connection with said selector and another motion transmitting connection with said Amotion interruptor, the two last mentioned connectionsjbeing interconnected to effect a motion transmitting position of said interruptor when said selector is driven from said feed branch line.

13. A milling machine as specified in claim 12 including a iiuid operable shifter for said motion interruptor, and a. valve controlling the operation of said shifter, said valve and shifter constituting a, portion of said motion transmitting connection to said motion interruptor.

14. In a milling machine, the combination of a rotatable tool spindle, a support therefor, a work table reciprocable adjacent said spindle in a path' transverse to the spindle axis, a spindle transmission including a power source and a motion interruptor, a table transmission including a feed rate branch line and a quick traverse rate branch line each driven from said spindle transmission exclusive of said motion interruptor, each of said branch lines providing terminal elements, selector clutch means shiftable to selectively engage the feed line terminal element or the quick traverse train terminal element, and a train driven through vsaid clutch means and including a shiftable reverser clutch having two positions respectively productive of different directions of table movement, a controller for shifting said reverser clutch, a dog ixed on said table for operation of said controller, a second controller, and means operable from movement of said second controller for shifting said selector clutch means, means operable from said second controller for operating said motion interruptor.

15. A milling machine as specified in claim 14 in which the-last mentioned means includes a pump driven from said power source exclusive of said motion interruptor, a shifter connected with said motion interruptor and adapted to be operated by the means of iiuid .from said pump, and valve means controlling the admission of uid to said shifter from said pump.

FRED A. PARSONS.

CERTIFICATE OF CORRECTION.

Patent No.` 2,040,528. A May l2, 19,56.

' FRED A. PARSONS.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as Afollows: Page 6, first column, line 51. claim 1 strike out the article "the"; page '7, first column, line 14, 'cla-im 5, before "selector" insert the words and comme. motion intermgtor, and that the said Letters Patent should be read with these correcf'os therein that the same may conform to the record of' the case in the Patient Office.

Signed and sealed this 18th day of August, A. D. 1936.

Henry Van Arsdale (Seal) Ating Commissioner of Patents. 

